The purpose of this proposal (part of Dr. Judith Brook's ongoing RSD Award) is to study the generational transmission of early childhood precursors of adolescent drug use. This longitudinal prospective study began in 1975 (T1) when first generation (G1) mothers assessed one of their children (ages 1-10) in terms of personality/behavior. Data were also obtained on family context and parent childrearing variables. Eight years later (T2) when G2 children were 9-18, mothers and children were reassessed, followed by a third data collection two years later (T3). At the T2/T3 data collections, the original T1 measures were repeated and additional data were gathered from both mother and child on personality/behavior, parent-child relations, and drug use. Having established with the T1-T3 data that childhood factors do influence later drug use, we propose to further investigate these influences by studying the G3 offspring of the G2 original study child. The G3 child will be evaluated at age 2 in terms of childhood precursors of later drug use. We will then trace the intra- and intergenerational pathways (T1-T4) to determine how drug-prone characteristics are transmitted. The hypothesized pathway, based on our Family Interactional Theory, is that parent personality risk characteristics (unconventionality, poor adjustment, poor control of emotions, and interpersonal difficulty) lead to parent-child mutual detachment (e.g., less warmth, more conflict). This then leads to the development in the child of risks for drug use. We hypothesize that this pathway, already shown in the G1 parent and G2 child, will be repeated for the G2 child (now a parent) and his/her G3 offspring. Also of interest is our proposed examination of risk (drug- conducive) and protective (nondrug-conducive) intra- and intergeneration interactions as they affect G3 child outcome. Our hypothesis is that protective characteristics (e.g., strong parent-child attachment) can buffer the negative impact of risk. The sample size for the proposed study will be 250 2-year-olds (50 per year), and both parents (500). T4 data will be collected using self-report, test situation, and observational procedures. Only psychometrically sound scales will be used. The analytic techniques will include structural equation and hierarchical regression. The significance of the study lies in its delineation of generational factors implicated in the development of childhood precursors of drug use. By focusing on ways to improve the psychosocial environment of the young child at risk, one can not only lessen the likelihood of later drug use, but also effect changes that will "break the chain" of generational risk transmission.